How critical is matching the coil?

[Peter Headland]

I am considering having an abominably noisy Goodmans CK-60 5 ton condenser replaced with a Carrier 38HDL 5 ton unit.

I know that the condenser and coil should always be matched for optimal performance and efficiency. On the other hand, using the existing coil (don't know the exact model) would save a bunch of money. Since this is not an area where humidity or extreme temperatures are any kind of concerns, just how big a problem would using a mismatched set be? In other words, is this such a bad idea I shouldn't even consider it, will I simply be looking at a slight degradation from perfect, or something in between?

If I have to change the whole set, I guess I ought to go to R22. Am I right to think that definitely means new pipework (= more $$) because of the higher pressure needed?

[HVACGuyInNH]

Well, without knowing the particulars on your situation (age of existing equipment, SEER rating, etc) I would say that the chances are that you'll have to replace the indoor coil.

[Gunnery Sergeant Hartman]

Do it right the first time.

It may cost more money up front today, but will cost you less to own over the next few years.

[motoguy128]

You may have incompatability problems. you mention "going to" R22.... meaning you have what R12 now? best to replace both and go to R410a since R22 is being phased out.


That being said, my system had a 25+ year old Chrysler indoor coil with a 15 year old Bryant condensor. It ran fine for 15 years. Electric bill in the summer wasn't that bad. Humidity removal seemed fine. I'm guessing the coil used to be R12 and was switched to R22.

[beenthere]

He has R22 now,

He just mistyped what he meant.

[heaterman]

Could you (your contractor) make it work? Possibly. Should you? Probably not. The loss in efficiency alone would be reason enough not to. Alot depends on the coil that is actually installed, if it's a newer 13 seer coil with TXV it may work out, ask your contractor's opinion.

[Shamoke]

Save yourself much possible trouble and expense in the near future and replace the coil and line set now with the condenser. I'd go with the R410a system now as well as it will be more efficient than an R-22 system.

You run the risk of incompatibility between the evaporator coil and the condensing unit if you try to hold onto old pieces of your system.

[diverdan]

You'll definitely lose efficiency if you don't change out the evaporator (indoor) coil at the same time. You can use the same line set. Some say you must clean the line set with RX11 Flush or equivalent and others have said you don't need to clean the line set, unless you've had a compressor burn out, which you haven't.

[tinner73]

Save yourself much possible trouble and expense in the near future and replace the coil and line set now with the condenser. I'd go with the R410a system now as well as it will be more efficient than an R-22 system.

You run the risk of incompatibility between the evaporator coil and the condensing unit if you try to hold onto old pieces of your system.

more efficient huh? why?

[amd]

13 SEER is 13 SEER, R-22 or 410a.

If the existing unit is also 13 SEER, it might work okay.

[Shamoke]

R410a is reported to be 5% more efficient than R22, thats why. I might also add that R22 is being phased out and the price is already rising steeply, so any new R22 systems installed today will find it hard to compete 5 to 10 years down the road when they start needing repairs.

[beenthere]

R410a is reported to be 5% more efficient than R22, thats why. I might also add that R22 is being phased out and the price is already rising steeply, so any new R22 systems installed today will find it hard to compete 5 to 10 years down the road when they start needing repairs.

The refrigerant is.
But, a 13 SEER is still a 13 SEER no matter which gas it is.

R22 is being phased out. But will still be make for 10 years yet.
Along with recycled R22 being available.

[Shamoke]

The refrigerant is.
But, a 13 SEER is still a 13 SEER no matter which gas it is.

R22 is being phased out. But will still be make for 10 years yet.
Along with recycled R22 being available.

It will continue to be made but in less and less quantity as time goes by. It has already doubled in price in less than two years and that trend will continue. The industry is moving forward with the transition from R22 to R410a and there is no reason, in my mind, to continue to resist the momentum forward.

R-22 is going to continue to hang around for a good bit yet but it's days are numbered and it's appeal will continue to lose it's luster. R410a will continue to come down in price and become relatively cheap compared to any other refrigerant choice available. Last I checked R22 was around two hundred a 30lb and R410a was two-thirty for a 25 lb, so 6.6 and 9.2 per pound respectively. That spread will only close and then widen the other way as time passes. I predict the prices will meet in another year or so.

The accelerated phase out of all HCFC refrigerants is driving the price up and by 2015 there is planed to have the north American market for all HCFC refrigerants reduced by 90%. Thats only 6 years, so I really don't see any reason to continue to buck the trend. there is another replacement choice for R22 in R427a but it, as yet, does not have the inductry backing that R410a has but it is supposed to be a drop in replacement from what I have heard so we will see what comes of it.

Just my five cents worth, take it or leave it.